Embree
automatic strapping machine



Nov. 21', 1967 H. K. EMBREE 26,307

AUTOMATIC STRAPIINCI MACHlNE Original Filed Oct. 2. 1961 17 Sheets-Sheet 3 FIG. 5

INVENTOR HAROLD K. EMBREE ATTORNEYS Nov. 21, 1967 H. K. EMBREE 25,307

AUTOMATIC STRAPPING MACHINE Original Filed Oct. 2, 1961 1'? Sheets-Sheet z J INVENTOR HAROLD K. EM REE ATTORNEYS NOV. H. K} EMBREE R6. 26,307

AUTOMATIC STRAPPING MACHINE Original Filed Oct. 2. 1961 1'? Sheets-Sheet 1* INVENTOR HAROLD K. EMBREE BY- jW 7 W"- ATTORNEYS Nov. 21, 1967 H. K. EMBREE Re. 26,307

AUTOMATIC STRAPPING MACHINE Original Filed Oct. 2, 1961 1'7 Sheets-Sheet 4 INVENTOR HAROLD K. EMBREE B M W ATTORNEYS NOV. 21, M R Re. 26,307

AUTOMATIC STRAPPING MACHINE Original Filed Oct. 2. 1961 17 SheetsSheet E I, I37 I30 FIG. H

INVENTOR FIG. 10 HAROLD K. EMBREE BY- M W ATTORNEYS NOV. 21, 1967 EMBREE Re. 26,307

AUTOMATIC STRAPPING MACHINE Original Filed Oct. 2, 1961 17 Sheets-Sheet 6 INVENTOR HAROLD K. EMBREE A rto EYS NOV. 21, 1967 H. EMBREE Re. 26,307

AUTOMATIC STRAPFING MACHINE I07 Jwoa I05 92 9 INVENTOR HAROLD K. EMBREE BY- Mr W ATTORNEYS Nov. 21, 1967 H. K. EMBREE AUTOMATIC STRAPPING MACHINE 1T Sheets-Sheet 8 w mb 2 2 mmv k2 N2 Original Filed Oct. 2, 1961 69 mg m? INVENTOR HAROLD K. EMBREE ATTORNEYS.

H. K. EMBREE AUTOMATIC STRAPPING MACHINE Nov. 21, 1967 Original Filed Oct. 2, 1961 17 Sheets-Sheet a HAROLD K. EMBREE ATTORNEYS 1'7 Sheets-Sheet 'l O Original Filed Oct.

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AUTOMATIC STRAPPING MACHINE Nov. 21, 1967 1'? Sheets-Sheet 1 L Original Filed Oct. 2. 1961 FIG. 18

INVENTOR HAROLD K. E MBREE ATTORNEYS NOV. 21, 1967 H K, EMBREE Re. 26,307

AUTOMATIC STRAPPING MACHINE riginal Filed Oct. 2, 1961 1. SheetsSheet HT I 329A E ass [Zr 1 Q 4 I 3968 396 33A /52I6 VET M h J 396/7 39? A Q L EQA /52Z 3409 5 /L F LT 2/4 343A J W528 FIG. 20 n INVENTOR HAROLD K. EMBREE BY W ATTORNEYS NOV. 21, H EMBREE AUTOMATIC STRAPPING MACHINE 1'7 Sheets-Sheet 14 Original Filed Oct.

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INVENTOR HAROLD K. EMBREE ATTORNEYS Nov. 21, 1967 H. K EMBREE Re. 26,307

AUTOMATIC STRAPPING MACHINE Original Filed Oct. 2, 1961 17 Sheets-Sheet W P-XXVI FIG. 24

INVENTOR HAROLD K. EMBREE ATTORNEYS United States Patent Ofifice Re. 26,307 Reissued Nov. 21, 1967 Matter enclosed in heavy brackets appears in the original patent but forms no part of this reissue specification; matter printed in italics indicates the additions made by reissue ABSTRACT OF THE DISCLOSURE An automatic strap applying machine feeds wire strapping through a loop forming frame, draws the tlin.r formed loop tightly about a package, knots the tight/ydrawn loop and severs it from the wire strapping supply. The loop forming frame is specially constructed to facilz tate wire feeding tlzerethrough.

The present invention relates to automatic strapping machines of the type used for example for applying wire straps to bales of paper pulp.

The invention particularly relates to a fully automatic strapping machine which, when initiated, applies a strap in form of a loop to a package, tensions the strap about the package and knots the strap all without the necessity of intervention by the operator.

In the past, wire tying machines have fallen into three general categories, firstly, the type where the strap is applied largely by the operator who manually operates hand tools to tension and knot the strap about the bale, secondly the type in which a loop is formed by a machine applied to the package and then tensioned and tied by the operator, and, thirdly the type in which a loop is formed by a machine and applied under tensions.

The devices of the prior art have suffered from several disadvantages not the least of which was a great waste of strapping material after the formtaion and severing of the strap. A disadvantage of the first two mentioned machines was that, owing to the bulk and clumsiness of the machines and the amount of manual exertion required by the operator in order to form the strap, operators were considerably fatigued after a working shift and production was relatively low for the length of man-hours involved in the operation, whilst a disadvantage of the further type of machine was that, owing to the strap being applied under tension the strapping curled. Thus when the strap was cut from the bale, it was often hazardous to the cutter because of the inherent uneven curl in the strap.

The present invention has to a very large extent overcome operator fatigue by providing a machine which is automatic and requires no eflort on the part of the operator other than the pushing of a button to start the machine in order to cause the formation of straps about packages or bales.

Applicant has further overcome the disadvantages of the prior art by providing a machine in which substantially all of the strap applied about the package is used for the purpose of strap formation, thus eliminating waste of strapping material.

Still furthermore according to this invention, the strap is applied in an unstrained condition.

According to the present invention, an automatic strap applying machine for use with a reel of wire or the like comprises strap feeding means, loop forming means adapted to receive the wire from the feeding means and Cir form a loop about the package when in place in the ma chine, strap tensioning means for tensioning the formed loop about said package and twisting means operable to form a knotting twist to overlapping ends of the loop, and cutter means operable to sever the knotted loop from the reel, all of which means are capable of being operated automatically and in a predetermined sequence.

A further feature of the present invention is to provide a conveyor means associated in a timed relationship with the strap applying machine in such a manner that a plurality of straps may be applied to a package in a predetermined sequence.

The following is a description by way of example with reference to the accompanying drawings in which:

FIGURE 1 is a pictorial view of the strap applying device, certain parts having been removed for the purpose of illustration;

FIGURE 2 is a view of the console seen from the rear with the rear cover removed;

FIGURE 3 is a section through the feed and tensioning roll showing the details of the mountings of those rolls;

FIGURE 4 is a pictorial view of the loop-forming strapping guide mounted in its supporting frame,

FIGURE 5 is a schematic plan view on a distored scale, of the loop-forming device indicating the manner in which the wire strap is caused to overlap for knotting;

FIGURE 6 is a detail of a corner of the loop-forming device;

FIGURE 7 and FIGURE 8 are front and side views, respectively of the main frame and the linkage for moving the support frame and loop-forming guideway therewithin, part of the front panel of the main frame having been removed to illustrate parts of the guideway;

FIGURE 9 is a detail of a section taken on the line IX-IX in FIGURE 7;

FIGURES 10 and 11 are details of the stripping device taken on the section lines X-X and XI-XI of FIGURE 6 respectively;

FIGURE 12 is a front view of FIGURE 13 is an end view FIGURE 14 is a detail in URE 13:

FIGURE 15 is an end view of the gripper from the end opposite that shown in FIGURE 13;

FIGURE 16 is a plan view of the gripper;

FIGURE 17 is a detail of the twister looking from the right as seen in FIGURE 1 and with the side plate removed;

FIGURE 18 is a plan view of the gripper and twister with the latter disengaged from the wire.

FIGURES 19 and 20 together form a schematic circuit diagram for the wire applying device;

FIGURES 2i and 22 are elevation and plan views of the conveyor device;

FIGURE 23 is a schematic illustration of the circuit diagram which can be roughly considered to continue beheath the diagram formed by FIGURES l9 and 20 but for the purposes of the description certain items in FIG- URE 19 have been duplicated in FIGURE 23:

FIGURE 24 is a plan view of a wire arrester for the device as illustrated in FIGURE 1;

FIGURES 25, 26 are sections in the lines XXVXXV, XXVI-XXVI respectively on FIGURE 24;

FIGURE 27 is a pictorial view of the links in the conveyor chain;

FIGURE 28 is a detail of the conveyor device;

FIGURE 29 is a detail of the cutter looking in the same direction as in FIGURE 7.

With the present embodiment of the invention a bale to be strapped is fed into strapping position within a rec tangular loop forming frame. Wire strapping is automatithe gripper device; of the same gripper device; lines XIV-XIV of FIG- TENSION AND FEEDING HEAD A console panel is located at one side of the loop forming guide member 32 and extending from the console panel is a motor-driven shaft 43 adapted to receive a reel 44 of wire strapping 45. The [drum] reel is driven by a. reversible motor 60 (see FIGURE 2) and the strapping 45 is adapted to be entrained over a guide roll through a pair of tensioniug rolls 51 to a pair of feeding rolls 55 by which it is fed into the loop-forming guide member 32.

The reversible motor is coupled to the shaft 43 for the [drum] reel 44 through a gear box 61, gear wheel 62, chain drive 63 and gear wheel 64.

The tension and feeding head 30 on which are mounted the guide roll 50, the tcnsioning rolls 51 and the feed rolls 55 is slidably mounted in guidcways on the front of the console 40 for reciprocation on the console 40 towards and away from loop forming guide member 32. A tension head pneumatic locking cylinder 65 engages a stop in the head at the front of the console and is operable to lock the head 30 in its outward position.

The lower tensioning and feeding rolls 51A and 55A are secured to the head 30 and move therewith. These rolls are driven by a motor 67 (FIGURE 2) through a belt drive 68, a sprocket 69 and a chain drive 70 through gears 71 and 72. The shaft 515 of the lower tensioning roll 51A is provided at its inner end with a sprag 635 (FIGURE 3) which permits of rotation of the roll 51A in one direction only. The shaft 518 is coupled to the sprag through the slip clutch 75 which is arranged to slip at a torque predetermined by a nut and washer arrangement 76 of known form. The shaft carries an arm 77 which is connected to a lever 78 (FIGURE 2) pivoted at 73? to the inside of the console front wall. The top of the lever 78 is arranged to contact a limit switch 320 when the head 30 moves towards the loop-forming guide member 32 due to the application of tension to the strapping sufficient to cause the head 39 to walk along the strap and to overcome the bias of a compression spring (not shown). The purpose of the switch 320 and the movement of the head 30 to operate it will become apparent hereinafter.

The top rolls 51B and 55B are mounted on eccentric shafts (FIGURE 3), are driven through gears 51G, 51E and are rocked down into operative position with the rolls 51A and 55A by a pair of reciprocating air motors 65 and 66 through levers 65C and 66C on actuation of the air motors.

LOOP-FORMING GUIDE The loop-forming guide member 32 (FIGURES 4, 5, 6, 7, 8) comprises a guideway having a channel or groove 90C in its outer edge, which guideway 90 is securely mounted in a rigidifying frame 91 and arranged for bodily movement therewith within a main frame 92 towards and away from the front thereof. Guidcway 90 comprises an entrance portion 95, a first upright portion 96, a top portion 97, a second upright portion 93 and a return portion 99. Reference to FIGURE 5 will show that the entrance portion 95 and the return portion 99 are spaced apart from each other. The spacing is caused by the offset in the top portion 97 and this offset is exaggerated in FIGURE 5 for the sake of illustration. The distance D between the entrance portion 95 and the return portion 99 is in fact not much greater than the width of the strapping wire. This offset enables the return portion of the strap to be led second upright portion 98 and return behind the entrance portion of the strap and thus to provide at the centre of the bottom of the guideway 21 pair of parallel running strap sections which in the strapping operation are twisted to form a knot.

When the guideway 90 is in the forward or loading position the channel therein forms with the front panel 100 of the main frame a closed track for the strapping wire and the front panel 100 prohibits lateral movement of the strapping wire out of the channel.

The guideway 90 has rounded corners and at these corners recesses are cut into the outer surface of the guideway to receive the periphery of rollers 136 (see FIGURES 6 and 11) mounted on the rigidifying frame 91. In this manner the strapping wire when being threaded into the channel 90C in the front face of the guideway 90 has a relatively friction-free passage around the guideway since it runs on the rollers 136 at the corners.

The offset in the top portion 97 of the guide is compensated for by variation in thickness in the front plate 100A of the main frame 92 so that the front plate presents a flat and level configuration to an outside observer.

As best seen in FIGURE 7 (which shows the main frame with the left-hand lower side of the front panel 100 removed) a gap exists between the entrance portion 95 and the return portion 99 of the guideway 90 and the entrance portion 95 does not extend beyond the centre line of the guide member 32 in the direction of the feeding rolls. This gap is closed and the guideway 90 thus completed by a tiltable feeding track arm 105, biased downwardly by a spring 1055, and a gate 106 (see also FIGURE 9). The feeding track has a strappingwire receiving-channel in its upper surface and it is into this channel that the strap is fed by the tension and feeding head 30 from the reel 44. The gate 106 has a tip in its inner surface to provide a complete loop-forming guideway for the strapping wire. The front run 45F of strapping wire, when it leaves the feeding track member 105, passes beneath a lip 106C of the gate 106 on top of an under-guide 104 and is separated from the rear run of strapping wire 45B by a barrier or separator member 94.

The frame 91 is 6, '7 and it at one;

provided, as best seen in FIGURES 4, of its corners with outwardly extending stub shafts 110, 111, 112 and 113 which, when the frame 91 is in place on the main frame 92, extends through apertures in the side plates 1005 of the main frame (FIGURE 6).

The stub shafts 110, 111, I12, 113 are connected externally of the main frame 92 to a linkage 115 comprising links 116, 117 and 118. Links 116 and 117 are connected at their tops by a double crossbar 119 which through a shaft 119$ connects with a single crossbar 119A to the link 118. Links 117 and 118 carry pivoted bell cranks 111B, 111C, 111D, 111E which engage shafts 110, 111, 112 and 113. Link 116 is connected through hell crank lever 116C to an air motor 114. The frame 91 is mounted on rollers in the bottom of the main frame 92. One of the rollers 91R is seen in FIGURE 9. Operation of the air motor 114 when a loop of strapping has been formed causes the link 116 through crossheads 119 and 119A to move links 117 and 118 which through hell crank levers 111B. 111C, HID, 1115 bodily displace the frame 91 which its guideway 90 comprising its en trance portion 95, upright portion 96, top portion 97, portion 99, back wards on the rollers 91R Within the main frame 92 away from the front plate 100A. At the same time, the frame 91 carries back with it a depending member 108 (FIGURE 9 which pulls on the link 109 to rock the link 107 and thus the gate 106 is rocked back clear of the front run of strapping wire 45F and leaves this run resting on the guide 104.

Mounted around the periphery of the frame 91 are a plurality of stripping pins 120 for stripping the formed loop from the guideway 90. These pins are completely free to slide in slots 121 (see FIGURES 6 and 10) in housings 122 on the rigidifying frame 91 and in slots 123 in the guideway 90. The pins extend beyond the frame at front and rear so as to be constrained within the main frame 92 by the front plate 100A and the rear plate 100B thereof. The pins 120 are undercut rearwardly at 125 and extend into the path of the guide channel C the undercutting providing for the loading of the straps into the channel 90C of the guide 90 when the frame 91 is in the forward position. It will be seen that when the frame 91 is moved rearwardly within the main frame 92 by the action of the air motor 114 the pins 120 cannot move since they abut against the rear plate B and thus the guide 90 moves relatively to the pins and the notches in the pins, which engage the strapping wire in the channel 90C, strip the strapping from the channel 90G of the guide 90. It is in this manner that the strap formed into loop configuration is removed from the loop-forming device 32. This stripping action is assisted by the spring loaded corner rollers (FIGURE 11) which are biased outwardly of the frame 91 by springs 131. When the frame 91 is in the forward position the rollers 130 are retracted in their housings 134 and offer a smooth periphery 135 to the Wire 45 in the channel 90C so that they cooperate with the fixed rollers 136 in providing for a smooth corner passage for the strapping wire but when the frame 91 is moved rearwardly the flanges 137 on the rollers 130 assist the stripping pins to expel the strapping wire from the channel 90C and to allow the removal of the excess strapping formed in the loop so that it conforms to the sides of the package before the centre portion of the wire is released onto the bale.

In order to ensure that the strapping wire is free of the guideway 90 at all points before it is pulled, by the action of the tension rollers 51 onto a package, a retaining device 800 (FIGURES 1, 24, 25, 26) is provided to momentarily restrain the strap after stripping.

The retaining device 800 comprises an endless tubular member 801 which provides a pair of closely arranged stops 802, 803 which extend across the front of the strapping device and encircle the upright sides thereof. A pair of perforated racks, one of which is shown in FIGURE 1 and indicated as 805, are provided, one on each side of the strap applying device and the height of the member 800 of the device can be adjusted merely by removing the pins 806 and moving the member 800 up or down and replacing the pins 806 in selected holes. It is necessary to adjust the height of the retaining member 800 in order to accommodate different size of bales. When the wire has been stripped from the guide member it falls between the stops 802, 803 and is momentarily arrested by the action of the plunger 807 against the depending face 808 until the action of the tension rollers 51 pull the strap past the plunger 807 and onto the package.

THE GRIPPER The gripper head 34 (FIGURES 12 through 16) is located at the centre of the loop-forming guide member 32 on a base plate having a front wall 150F and side walls 1505. The base plate 150 has vertical gibs 151 extending upwardly therefrom behind the front wall 150F. A supporting frame 152 is mounted for vertical reciprocation in the gibs 151. The supporting frame 152 is vertically reciprocated by the piston and cylinder airmotor 153. The extremity of the piston rod 153R is provided with a clevis 154 to which is attached a link 155 connected to shaft 156. Mounted on the shaft 156 is a link 157 having a bifurcated end 158 which engages with a crank pin 159 on the supporting frame 152. Extension of the piston rod 153R in the cylinder 153 rocks the link 155, the shaft 156 and the link 157 to raise and lower the supporting frame 152 and the gibs 151.

Connected to the top of the top of the supporting frame 152 is a traversely extending shaft 160. Mounted on the shaft 160 so that it may rock about the axis thereof relative to the supporting frame 152 is a gripper head assembly 161. The gripper head assembly 161 comprises: a fixed upper gripper jaw 162. having a stop face 162F; a tilting frame 163, to which the jaw 162 is firmly connected and a moveable lower jaw 164. The jaw 164 is raised and lowered into closed and open position by a pneumatic cylinder and piston arrangement 165. The clevis 167 on the outer end of the piston rod of this arrangement is connected through a clevis pin 170 to a link 168 which is connected through an eccentric 169 to the jaw 164 (FIGURE 14). Actuation of the cylinder causes the rocking of the arm 168 on the eccentric 169 about a pivot point 1681 providing for the raising and lowering of the gripper jaw 1.64.

Extending from the rear of the clevis pin 170 is a conical cam engaging surface 171 (FIGURES 13, 15 and 16) rigidly secured to the base plate 150 is a projecting bracket 172 carrying a cam face 175.

The gripper assembly 161, in addition to being mounted for rocking action about the shaft 160 is also arranged for limited axial movement on the shaft against the bias of the spring 175. On the end of the shaft 160 remote from this spring 175 is provided a bracket 176 carrying a switch 395 which is actuated by a trip element 177 on the frame 163. Thus, relative movement of the frame 163 axially of the shaft 160 to the switch 3195 (caused by the action of the leading end of the strapping wire being fed into the gripper assembly 161 to abut against the stop face 162F) causes the member 177 to engage and trip the switch 395.

Extending across the front of the supporting frame 152. and rigidly attached thereto, is a projecting member 180 to which is attached a bushing 180B carrying a goosenecked guide finger 181 mounted for rocking about the bar member 180 and spring biased by a torsion spring 1818 into a normally inward position. The goose-necked guide finger 181 is provided with a slot 185 which engages the front run 45F of the wire 45 in the guide member 32 through slot 1065 in the gate 106. Also attached to the frame 152 at the end remote from the guide finger 1.81 is a front lift finger 186 for the front run 45F of the strapping wire. Behind and pivotally attached to the finger 186 is a rear lift finger 187 (FIGURE 15) provided with a strapping wire engaging slot 188 and a bumper pad 189.

Mounted on the back of the tilting frame 163 is a switching arm 190 connected to the eccentric 169 and a switch 191. Operation of the piston and cylinder arrangement 165 to rock the arm 168 to open the jaw 164 causes the switching arm 190 to engage with a trip the switch 191 for the purpose which will become apparent hereinafter.

Mounted on the base plate 150 at the rear thereof is a switching panel 193 carrying three switches 328, 329. 397 operated by a cam bar 197 having three switch tripping cams 328c, 329c, 397c thereon. The cam bar 197 terminates in a bifurcated link 197L which is connected to the lower end of a bell crank lever 198. The bell crank lever 198 is pivoted at 198p to the panel 193 and at its upper end is connected to the pin 199, and then through a crank lever 200 to the shaft 156. Thus, when cylinder 153 rocks the shaft 156, it, in turn. moves the cam bar 197 through the bell crank lever 198 to slide the cam bar 197 so that the switches 328, 329, 397 are operated by their tripping cams.

Secured on the frame 163 adjacent the gripper jaw 162 is a hollow trunnion 205 (best seen in FIGURE 13) which carries a guide lever 206 pivotally mounted there on. At the lower extremity of the guide lever 206 is a roller 207. Midway on the lever is a slot 208 which engages with a stub shaft 209 which is fixed to the frame 163. Adjacent this point the lever is engaged by a spring pressed plunger 210 housed in a bracket 211 on the frame 163. The guide lever 206 functions to return the 

